You are asking a broader question which gets multiple answers and endless debate []. I would suggest what kind of technical areas you wanted to know the difference, I will nto suggest the relevant Vendor sites...but there are few good blogs out there which can give some perspective to the discussion.

We published a very detailed four part article on this not so long ago - starts at http://www.sql-server-performance.com/articles/dba/oracle_sql_server_comparison_p1.aspx. Just use the site search to get all four parts.

It is one of agrumentative question that I see on the forums.
As for you it is more on technical research the best bet is to go through their sites such as Microsoft & Oracle for any whitepapers, where you will find the obvious CAT & MOUSE play [].
So referring the blogs you can go thru:http://www.infoworld.com/d/data-management/oracle-vs-sql-server-758
Also I can't remember on which site it is referred, this is one of best response:
Both the products are excellent on their own featuers. How they perform and scale is dependent upon the following (in this order)

The quality of the database design your developers create, including indexes.